There is no confirmation from authorities whether this latest discovery increases the number of people killed, which stands at seven, including the gunman.

UPDATE 8:54 pm: The three victims found in the apartment were stabbed to death. Their deaths were included in the previously-reported death toll of 7.

Meanwhile, KEYT has obtained a 140-page manifesto reportedly written by Rodgers titled "My Twisted World." It was sent to the station by an "acquaintance who had something to do with bodybuilding," according to KEYT reporter Tracy Lehr.

"On the day before the Day of Retribution, I will start the First Phase of my vengeance: Silently killing as many people as I can around Isla Vista by luring them into my apartment through some form of trickery," the manifesto reads in part.